Circular motion

Question 1

radian = ?

Answer 1

arc-length / radius

Question 2

angle in radian = ?

Answer 2

degree x pi/180

Question 3

angular speed

Answer 3

is the angle an object moves through per second w = x/t w = arc-length / radius x t = v/r. unit is rad s-1

Question 4

frequency

Answer 4

is the number of complete resolutions per second

Question 5

period

Answer 5

is the time taken for a complete revolution

Question 6

f = ?

Answer 6

1/t

Question 7

for a complete circle, w = ?

Answer 7

2 pi/t 2 pi f

Question 8

centripetal accelaration

Answer 8

objects travelling in circles are accelerating since their velocity is changing. even if the car is going at a constant speed, its velocity is changing since its direction is changing. it is always directed towards the centre of the circle. unit is ms-2

Question 9

a =

Answer 9

v^(2)/r = w^(2)r

Question 10

newton first law

Answer 10

an object’s velocity will stay the same unless there’s a force acting on it

Question 11

centripetal force

Answer 11

since an object travelling in a circle has a centripetal acceleration, there must be a force causing this acceleration. it acts towards the centre of the circle = mv^(2)/r = mw^(2)r. unit is N